相关论文: Impact parameter dependence of parton densities at…
We study the orbital angular momentum structure of the quarks inside the proton. By employing the light-cone diquark model and the overlap representation formalism, we calculate the chiral-even generalized parton distribution functions…
We establish the relationship between distribution and fragmentation functions and the structure functions appearing in the cross section of polarized 1-particle inclusive deep-inelastic scattering. We present spectator model evaluations of…
We study the Bjorken `x' (or equivalently Nachtmann `xi') dependence of the virtual photon spin asymmetry in polarized deep inelastic scattering of electrons from hadrons. We use an exactly solved relativistic potential model of the hadron,…
We present recent results on transverse momentum dependent parton densities in the limit of small Bjorken x. A definition of an unintegrated seaquark density is proposed which can be used within the CCFM Monte-Carlo event generator CASCADE.…
The Coulomb-hadron interference effects are examined at small and large $t$. The methods for the definition of spin-dependent parts of hadron scattering amplitude are presented. The additional contributions to analyzing power $A_N$ and the…
We present first calculations of the fluctuating gluon distribution in a proton as a function of impact parameter and rapidity employing the functional Langevin form of the JIMWLK renormalization group equation. We demonstrate that when…
A simple picture of the constituent quark as a composite system of point-like partons is used to construct the unpolarized and polarized parton distributions by a convolution between constituent quark momentum distributions and constituent…
We investigate structure functions in deep inelastic scattering processes (DIS) at Bj\"{o}rken limit and found that they are factorized into the longitudinal and transversal parts. We see that the longitudinal part can be linked to exact…
The relation between energy and density (known as the nuclear equation of state) plays a major role in a variety of nuclear and astrophysical systems. Spin and isospin asymmetries can have a dramatic impact on the equation of state and…
Some simple relations between unpolarized and polarized quark parton distributions have direct experimental consequences which will be presented here. In particular, we will see that it is possible to relate the deep inelastic structure…
The impact-parameter representation of the spin-flip amplitude of hadron elastic scattering is examined in different unitarisation schemes, taking the Born term of the spin-flip amplitude from the Dubna Dynamical Model (DDM). It is shown…
The implications of the positivity constraint on the presently unknown polarized structure function of the photon, $g_1^{\gamma}(x,Q^2)$, are studied in detail. In particular the non-trivial consequences of this constraint,…
We study the fragmentation of a transversely polarized quark into a non collinear (k_T not= 0) spinless hadron and the fragmentation of an unpolarized quark into a non collinear transversely polarized spin 1/2 baryon. These nonperturbative…
Deep inelastic structure functions for the nucleon are obtained in a constituent quark model on the light cone. Parton model formulas are derived. The negative slope of $F_{2}^{n}/F_{2}^{p} requires attraction between scalar quark pairs.…
The new definition of the energy dependence for the level density parameter including collective effects depends strongly on the semi-classical approach. For this method, defining an accurate single-particle potential is of great…
We propose two new sources of a substantial tensor polarization of sea partons in the deuteron: the diffractive nuclear shadowing which depends on the alignment of nucleons in the polarized deuteron and the nuclear excess of pions in the…
Using a simple picture of the constituent quark as a composite system of point-like partons, we construct the polarized parton distributions by a convolution between constituent quark momentum distributions and constituent quark structure…
The electron structure functions are studied in polarized $e^+e^-$ scattering. The formulae for longitudinally and transversely polarized electrons are presented. The smallnes of the electron mass leads to negligible cross-sections and…
The main goals of `spin physics' are recalled, and some theoretical and phenomenological aspects of longitudinally polarized deep inelastic scattering and other hard processes are reviewed. The spin dependent parton densities of protons and…
We propose a model for the unpolarized generalized parton distribution function (GPD) based on impact parameter representation and discuss its x and t dependencies at large and small values of these variables.